Strong chemical or musty odor from spa water.

Safety first: Avoid using the spa until water is clear and odor-free.

• Test and balance: Use test strips to check sanitizer, pH, and alkalinity. Adjust to recommended levels.
• Shock spa: Perform a shock treatment to break down chloramines and kill bacteria.
• Clean filter: Rinse or replace the filter cartridge.
• Plumbing cleaner: Periodically use a spa plumbing line cleaner to remove biofilm from hoses and internal passages, following product instructions.
• Drain and refill: If odor persists, drain the spa completely, clean the liner with a spa-safe cleaner, and refill with fresh water.

Warning: Do not over-chlorinate; extremely high chlorine levels can damage spa components and irritate skin and lungs.